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Since the time of Bentham, the "premier systematic botanist of the nineteenth century"[4] considerable efforts have been made to classify and understand the striking morphological diversity in Senecioneae.[1] The traditional view of the tribe has been that of one huge genus Senecio plus many other genera which exhibit varying degrees of distinctiveness.[4] Circumscription and delimitation of the tribe has experienced expansions and contractions over the decades as genera and groups of genera have been moved in and out,[2] as was the case for Arnica, Liabum, Munnozia, Schistocarpha, etc. which have since then been excluded.[4] Of the several potential causes for this constant redefinition the greatest is probably that little is known about its intergeneric relationships or a lack of phylogenetic understanding enhanced by the other problems of conflicting clues from morphological characters, the large size of the tribe, the absence of a precise delimitation or circumscription of Senecio[1] and the naturalness of these assemblages combined with the imprecise boundaries of the different species themselves.[4]

Many segregate genera have been recognized in recent studies, often with circumscriptions derived from selected representative species. It is yet unclear that the recognition of numerous segregate genera provides a better taxonomy than treating the variation patterns as infrageneric taxa. A respectable case can be made for maintaining Senecio as a broad concept, at least until revisionary studies at the species level are carried out and the results subjected to critical analyses.[4] Most genera that have been removed from Senecioneae in its broadest sense have come to rest within Liabeae or within a broadly circumscribed Heliantheae (e.g., allies in Arnicinae, Chaenactidinae, or Madiinae; Haploësthes in Flaveriinae; Raillardella and allies in Madiinae). Additional information may be found in B. G. Baldwin et al. (2002), H. Robinson (1981), B. Nordenstam (1977–1978) and K. Bremer (1994).[2]